Answer:
When I type I tap these on the keys
What is so delicate that saying its name breaks it?
Which weighs more? A pound of iron or a pound of feathers?
Man's most important invention.
What can run but never walks, has a mouth but never talks, has a head but never weeps, has a bed but never sleeps?
Though not a plant, has leaves. Though not a beast, has spine. Though many wouldn't need this thing, It's more valuable than wine.